Posted
by
timothy
on Saturday May 19, 2012 @06:56PM
from the simulated-only-do-not-attempt-keep-hands-in-cart dept.

This morning's nixed launch of SpaceX's Dragon capsule to the ISS with the company's Falcon booster was an exciting thing to be on hand for, despite the (literally) last-second halt. Shuttle launches used to cause miles of traffic backups extending well outside the gates of NASA's Cape Canaveral launch facilities; for all the buzz around the first private launch to the ISS, today's launch attempt was much more sparsely attended. In a small set of bleachers set up near the massive countdown clock, there were a few dozen enthusiasts and reporters aiming their cameras and binoculars at the launch site on the horizon. They counted down in time with the clock, and — just like NASA's own announcer — reached all the way to "liftoff." There was a brief flash as the engines ignited, but it died as fast as it appeared. It took only a few seconds for the crowd to realize that it was all over for today's shot. While the company's representatives remain upbeat, pointing out that the software worked as intended to stop a launch before anomalies turn into catastrophes, most of those on hand to see what they'd hoped to be a historic launch were a bit glum as they walked back to the parking lot and the press area — especially the ones who can't stay until the next try. I'm sticking around the area until the next scheduled launch window; hopefully next time the fates (and engines) will align.

Have any ideas at the likely to be possible in the next fifty years level?

Either that, or better buttstrap bombs. This is the problem with progress... it might be safer and (maybe) cost less with tomorrows technology, but that will still be true tomorrow too, and if you keep waiting for tomorrow you'll never get anywhere.

So if we want to go beyond the earth's atmosphere now we'll just have to keep strapping bombs to our butts.

Short of someone inventing wormhole technology, I don't think it actually gets any better within the laws of physics.:D It even beats out hypothetical space elevators in cost per kilo. Not in individual volume mind you, but one can always build more Star Trams.

.....(5) become a billionaire:)
I don't think the space elevator is a solid idea though. from my understanding, and please feel free to correct me, to make one you would need something like carbon fiber tubes or wire? i remember reading on ideas on how to make them. it seemed to me the biggest danger was something severing the wire and having it fall back to earth ( or so the article said). have they made any steps in a positive direction or have the launched any new ideas?

it seemed to me the biggest danger was something severing the wire and having it fall back to earth

Yes it will be like dropping 100 tons of paper from orbit. Very dangerous. It will never reach the surface before burning up though... And if it did, it would drop like leaves, slow, harmless and spread over a huge area of sea.

People seem to forget the whole point of using this still non-existing super strong material for the wire, is to have the strength even when it is stretched mind boggling long. It will have a huge surface to weight ratio. More than anything man or nature ever made before.

Yes it will be like dropping 100 tons of paper from orbit. Very dangerous. It will never reach the surface before burning up though... And if it did, it would drop like leaves, slow, harmless and spread over a huge area of sea.

Check out the documentation at startram.com. And then help spread the word! Evangelise! There's just so little awareness of it out there at the moment. Admittedly if it went wrong it wouldn't be pretty, but the engineers estimate one accident every 2800 years or so.

I have some problems with the principle of the Gen 2 design. The entire thing would be lifted up to 20km using magnetism? Not that I think it is impossible to create the necessary forces, I just wonder what would happen if I came anywhere close with a small magnet. How large would the impact crater be? Same with anything made of iron, or magnetic ores. It seems just based on a back of the envelope calculation, without examining other implications.

The entire design has been examined by Sandia National Laboratories and found to be sound, so pretty far from a back of the envelope calculation. Myself I'd have gone for pylons in support instead, but how and ever - Gen 2 is very far off. Gen 1 can not only be built rapidly, it absolutely will revolutionise space, and there are proposals on the table to produce a gen 1.5 thus removing the need for Gen2.

Sure, there are a number of technologies that can be developed for hauling cargo, another option is quicklaunch [quicklaunchinc.com]. No problem there at all. However that doesn't answer my question. But if there is a review of the design, I'd better first take a look at it first. Maybe they didn't cover the gen2 design? There is just one problem: there is no review to be found. If you go to the website of Sandia [sandia.gov], and search for startram, you get 0 hits. If you google for sandia national laboratories "murder squad" you only get

There's no comparison between a maglev launch system and what SpaceX is trying to do. Just for a start, the on-paper development cost for Startram rev 1 is 50 times greater than the development cost for everything SpaceX has done so far, and comparing the costs of an "on paper" system to a real flying system is... not a good idea. You're looking at a kid with a bicycle and saying "Y'know, you could get to the grocery store a lot faster if you bought a Boeing 777."

Eh all of that is well covered in the documentation, the pod exits the tube at mach 25 or thereabouts, and experiences 10-15g deceleration. If you can't distinguish that from a bomb I'm not sure what more can be said here. There is no explosion, no blast, and of course you're going to need high energy to get to orbit.

As for costs, SpaceX could spend 500 times more than they already have, and they still wouldn't be within an order of magnitude of what the Star Tram can do. Its not possible, due to the rocket

The second doesn't necessarily follow from the first. Space elevator designs typically involve using something like ground-based lasers to transmit power to the crawler, possibly using conventional conductors to power it for the bottom few km before resistance makes that too expensive. For a person, we're talking something on the order of 1MWh. If it is spread over 10 hours (which is far faster than any proposed space elevator design) then the power supply is only 100kW, which well below the upper limit of power distribution systems. Any office building is likely to have a larger amount of power coming into it. Just because you have to supply a large amount of energy, doesn't mean that you have to have the capability of supplying it all at once.

A claim that NASA is underfunded doesn't follow from the fact that space launch is expensive. As I note they can easily afford the current launch rate. One has to look at the whole budget not a small part. My take is that the money overall is spent very poorly making any such claim suspect.

Outreach such as that actually is one of NASA's many lesser job functions and it's not just focused on Muslims. That whole controversy comes from a Bolden fumble [foxnews.com] (the current NASA administrator) during a visit to the Middle East (and probably a result of some higher up, say Obama, telling him to say nice things while he was on the trip).

In any case, Bolden doesn't to my knowledge say such things any more which seems to have fixed that particular problem.

That only proves the system doesn't work and they haven't learned enough. What they need is a proper and reliable SSTO (single stage to orbit) space craft, some pioneering work in progress [wikipedia.org]. These SpaceX stunts are equivalent of the old days, when you could cross the Atlantic using a wooden bi-plane with a prop, but it was a huge stunt. Then the jet engine came and everything has changed. These space cowboys are just that, no real viable

That only proves the system doesn't work and they haven't learned enough.

Well, sure. But somehow you do have to get from point A where they don't know how to launch a rocket reliably to point B where they do. This is how that happens.

What they need is a proper and reliable SSTO (single stage to orbit) space craft, some pioneering work in progress.
Or a space elevator... maglev booster... nuclear thermal rocket... anti-grav device... telekinetic gestalt...

You have to work with what you have not what you wish you had. Currently, we haven't figured out a viable SSTO vehicle. Frankly, I think a fully reusable TSTO is both more likely to be achieved and actually technically superior in performance to a SSTO.

These SpaceX stunts are equivalent of the old days, when you could cross the Atlantic using a wooden bi-plane with a prop, but it was a huge stunt.

Because it doesn't use your pet technology, it's a "stunt"? This is tiresome and meaningless posturing. SpaceX is bending metal and pushing the economic envelope of cheaper space flight. Because nobody is doing it better means automatically it isn't a stunt.

Then the jet engine came and everything has changed.

You need a better grip on aviation history. Everything was changing before jet technology. There was a big change in the aviation industry and society in that span of time from the early days of the biplane to the advent of jet propulsion. Commercial airlines were developed during this time, for example, as well as extensive military development and use (such as the Second World War). It wasn't biplanes were made, then jets, and suddenly there we go.

It's also worth noting that without all that development of infrastructure, economic uses, and military deployment, there wouldn't have been much incentive to do anything with the jet engine. It doesn't magically become useful just because it's a new technology. The world was ready to exploit jet engines. That's why they were so popular and so heavily used.

You're using an insulting analogy with no real reason for to be insulting. Just as the world went through a biplane phase, we have to go through a rocket phase. So what? The key problems of today aren't technological, but economic. Without suitable economic demand for those launch services, you won't get development of your favorite space access technology.

That's where businesses like SpaceX come in. With their "stunts", they lower the cost of access to space and create more demand which can in turn fund better launch technologies. You want a SSTO? Better hope that SpaceX or some other launch business is successful with their stunts.

I wasn't aware that fiber optic ethernet communications systems using IPv6 and radiation hardened FPGAs using multi-core processors was 1960's technology. I could be mistaken on that notion however. That is just the guidance computer and the internal communications systems in the Falcon 9, much less the Niobium nozzles and the friction stir welded tanks that are used in the Falcon 9.

If all of that is 1960's tech, I'd hate to see what real 21st century technology would be like.

"Just as the world went through a biplane phase, we have to go through a rocket phase."

During the "bi-plane phase" there were numerous builders, some even home built, that pushed the technology along. Before the war was the commerce and thrill seekers that funded these efforts and out of them we got some amazing innovations, and some deaths (it was prize money that sent folks across the Atlantic, not national pride).

If I had a penny for every dollar spent on single-stage-to-orbit research that went nowhere, I'd be Bill Gates.

You can argue that SpaceX's Falcon rocket is "a huge stunt", but that huge stunt actually flies to orbit at a reasonable price. Your "pioneering work in progress" is nothing but a few megabytes of CAD files.

It's a fundamental fact of rocketry: if you can design a single-stage rocket, you can use the same technology to build a much better multi-stage rocket. All of this has been known for half a c

I've never seen a launch aborted this late before. The announcer had already said "Liftoff," and you could see the flames building up rapidly as usual. The rocket was only one second from moving off the pad when the shutdown command was triggered.

Gwynne Shotwell's quote in another article was a good one -- paraphrasing, she told the reporter that the launch wasn't really seen as a "failure," because that's what happens when you fail to catch a fault condition in time.

Just as any landing you can walk away from is a good landing, any launch that doesn't end with the rocket in a million flaming pieces is a good launch. They can try again in 3 days.

I was reading a on this earlier, (not sure if it is in the link) but SpaceX is actually using a new launch system that intentionally holds the rocket on the pad after ignition just so that additional telemetry can be gathered about the operating state of all the engines at power...

Not a bad idea. You waste only the tiniest it of fuel, while giving you just enough time to locate most failure scenarios (not all, by any means, but a lot of them). If you didn't hold it on the pad, even the relatively short distance it would rise would require you to continue liftoff (aborting later on, which is very dangerous), since even a tiny fall will destroy the rocket.

I forget which flight where this happened, but it seems like there was a very early NASA flight which did lift off the pad and land back down, only going just a fraction of an inch (or a few millimeters) before coming back down, then the engines shut off.

I also remember seeing several early flights where the rocket did lift off more than a few feet then came crashing back down... in some cases taking the launch tower out with the rocket. This particular procedure of holding the rocket down at launch has so

The implementation may be new (I don't know), but the idea isn't. Hold-down clamps have been around for a while, probably since at least the V-2 (A-4). The idea is to hold the thing down long enough for the engine(s) to build up enough thrust to lift properly, rather than just knock the rocket over.

The Shuttle had explosive bolts holding the SRBs down so the thing wouldn't blow over, either in a strong wind or when the SSME's lit. I'm not sure that they were strong enough to hold it down once the solids ignited, though (not that additional telemetry is going to do you any good at that point.)

These hold downs are pretty amazing. If you've ever watched recent shuttle launch videos you can see the top of the shuttle lurch a couple of feet laterally when the SSME's light up. It's pretty spectacular. I believe that the SRBS light a couple of seconds before liftoff, so the entire thing is held down for a second or two, even after SRBs lit.

The main difference between the Shuttle and the Falcon 9 as far as launch abort goes is that the SRBs cannot be shut down. As soon as they light, the launch has to happen. The SSMEs of course could shut down after ignition, and in fact did so on an occasion or two. Normally this would happen about T-6 seconds or so, unlike the T-0 shutdown of the falcon 9.

These hold downs are pretty amazing. If you've ever watched recent shuttle launch videos you can see the top of the shuttle lurch a couple of feet laterally when the SSME's light up. It's pretty spectacular.

Yes, it's pretty amazing, they do lift the thing up a good bit. The main engine is checked for proper operation, after which the SRB's are lit off. When the SRB's go, the stack is going to leave the pad, even if it takes it with it, so the explosive bolts have got to work.

There were launches where the main engines were shut down immediately after ignition. STS-41-D, STS-51-F, STS-51, STS-55, and STS-68. I believe the NASA term is "pucker string" moment.

I have lots of experience with the Shuttle hold down studs. The way they work is there are 4 conical hold down posts at the base of each SRB that are attached to the pad. A 3 ft long 4 inch diameter inconnel bolt goes through the SRB skirt and hold down post. A nut goes on the top and bottom. The preload in the bolt is over a million pounds. You would need a big torque wrench to get that but instead we use a hydraulic puller that stretched the stud and then you slightly tighten the nut and when you let go of the hydraulics the stud is nice and tight.

The stud doesn't explode. The top nut has two explosive charges in it. If either one goes the nut is split and the stud shoots out since its under such a high preload. There is a blast container that is supposed to prevent FOD. Each charge is handled by a seperate circuit. We did have a few cases where the studs didn't come out. It turns out there was a unknown failure mode. If the two charges went off with just the right delay you had a situation where the nut halves would bounce off their blast container and come back and hit the stud and the threads could catch just right slowing the stud down.

It was cool. We did about 30 tests shooting high speed footage with different skew delays in firing the charges.

But to answer your question. The studs are stronger than the aluminum aft skirt which would probrably be torn if more than one bolt failed to release. This would have been catastrophic.

Were there any contingencies if the nuts didn't blow and the rocket wasn't released? You also said there is a problem if more than one bolt didn't release - what would happen if only one bolt didn't release?

You are right about the lateral movement, but the shuttle stack doesn't just move laterally one way--it actually reverses (since the stack is still bolted to the pad) and the timing is such that when the SRBs fire, the stack is pointed true vertical again.

The SRBs are not held down once they fire though. Check out this incredible series of slow-motion video [youtube.com] from a lot of cameras you might never have seen footage from--it's like porn for space tech junkies. Jump to 6m28s for the first camera on the SRBs, which record the explosive bolts that hold the SRBs down. You'll actually see the bolts fire and release the SRBs a fraction of a second *before* we see the flames come out from the SRBs.

I posted earlier today about STS-68, which aborted the launch sequence at T-1.9 seconds, the closest to T-0 the shuttle ever got in an on-pad abort. There's a video of that launch attempt on Youtube too, but there's a second video (not on Youtube, unfortunately) showing the engines firing up and then shutting down. They actually flame out one by one, presumably to lessen the magnitude of the lateral motion that now lasts for several back-and-forth swings.

The implementation may be new (I don't know), but the idea isn't. Hold-down clamps have been around for a while, probably since at least the V-2 (A-4). The idea is to hold the thing down long enough for the engine(s) to build up enough thrust to lift properly, rather than just knock the rocket over.

They go back further than that... Both Goddard and Von Braun used them. Though back then the sensors were optical (does the rocket flame look right?) and the operation manual (pull the string that releases the

I've never seen a launch aborted this late before. The announcer had already said "Liftoff," and you could see the flames building up rapidly as usual. The rocket was only one second from moving off the pad when the shutdown command was triggered.

The earliest I can recall this happening was on Gemini 6's first launch attempt in Dec 1965.

Most liquid-fueled launchers have had this capability. It's important for any multi-engine launcher, in case not all the engines start. It's usually considered a requirement for man-rating a launch system.

That's actually part of the QA process that NASA requires. After any fault is identified, you must add a procedure for ensuring that faults of this nature are not problems in the future. In your example, this would require either adding kevlar tyres, or ensuring that the tyres were checked after backing out of the driveway and before starting the journey.

Right, like checking the driveway for nails before getting in the car.This is exactly the kind of thing that makes programs like this expensive as hell. Hopefully they avoided a major disaster and will continue to refine the program. This is indeed an important event that needs to be assimilated.

Title: Scheduled SpaceX Launch Scrubbed at the Last MinuteDescription: The kids whose experiment was scheduled to go into space were disappointed but not crushed by the delay

00:00) TITLEA SlashdotTV title animation appears.

00:05) TITLEThe view fades to that of Timothy Lord on the grounds at Cape Canaveral.

00:05) TimothyThis is not what anyone saw today on Cape Canaveral.

00:08) TITLEAn animation sequence of what was to be the SpaceX Falcon+Dragon launch is shown with "- animated simulation - do not try at home" repeatedly scrolling past in the bottom. Hereafter referred to as "SpaceX animated simulation".

00:19) TimothyInstead it was pretty darn disappointing when today's launch of SpaceX's Dragon capsule was nixed with just seconds on the clock.

00:25) TimothyAn early announcement said the abort was based on a high pressure reading in engine number 5.

00:29) TITLESpaceX animated simulation is shown.

00:33) TimothyAmong those disappointed by the launch were some students who were here all the way from Indiana to watch the launch of an experiment they've been working on since last October.

00:40) TITLEA shot of three kids at the Cape Canaveral facilities appears.

00:40) J.P.I am J.P. [last name]

00:42) CameronAnd I'm Cameron [last name]

00:44) JackAnd I'm Jack [last name]

00:45) J.P.We are from Highland, Indiana.We were here to see the Falcon 9 take off, with our experiment, for the International Space Station.

01:08) J.P.Astronauts were gonna perform the experiment, and then it was gonna be sent back down to Earth, and we were gonna also perform the experiment on Earth, and compare the results.

01:21) JackIt's an after-school extracurricular club that we have.

01:25) JackThe shirts we got from Pioneer [Pioneer Hi-Bred International, Inc -- ed.] who gave us a grant to come down here.They gave us the seeds, and so they gave us a grant to get some press for the shirts and stuff, and they gave us a grant to come down here - they paid for everything, so..

01:39) JackI'm not too disappointed because.. it's a space program and things happen, and we have Tuesday to look forward to - whether on TV or we get to come here - and we'll see what happens.

01:50) TITLESpaceX animated simulation is shown.

01:55) TITLEThe view fades back to Timothy on the grounds at Cape Canaveral.

01:56) TimothyThe next launch window is Tuesday, about 72 hours from now.Hopefully the fourth time's the charm, and we'll actually see both Falcon and Dragon take off.

The rocket launch animation in the video does not show the Falcon 9 rocket+Dragon but the not yet fully developed Falcon 9 Heavy (SpaceX [spacex.com]) which according to the SpaceX launch manifest will have a first test launch later this year (but I guess late 2013 seems more likely judging from SpaceX's previous track record of delays).

Lot of comments here saying that the SpaceX rockets are pretty much the same old technology as the 1950s, and why aren't we focusing on carbon fiber scramjet single-stage spaceplanes or flying saucers powered by dark energy?

Because two-stage kerosene-and-oxygen rockets *work*. It's proven technology, you *know* it's going to work, and you don't have to spend billions on aerodynamics research to figure out if it's going to outfly its own skin. [go.com] From there, you can add in high-tech electronics, advanced manufacturing, etc., as SpaceX has done.

This sort of practical solution to real-world problems using tried-and-true technology is something every engineer should appreciate. Including an engineer you all know and love. [teamfortress.com].

Lot of comments here saying that the SpaceX rockets are pretty much the same old technology as the 1950s, and why aren't we focusing on carbon fiber scramjet single-stage spaceplanes or flying saucers powered by dark energy?

Because research on new technologies is very, very expensive. And once the Space Race died down in the early 1970's, none of the governments that funded the research have seen any point in putting real money into them. Or, to put it in perspective, we're at the point aviation technolog

Always problematic to paraphrase Donald Rumsfeld, but you go to war with the army you have, not the army you'd like to have. You don't get to wish you had a new Apollo program so you could re-invent the rocket from scratch. Your goal, if you actually want to go to space instead of dreaming of the stars, is to make the best of the tools you have, improving them as you can.

they tend to fail about 2% of the time

I'm skeptical of this number. Got a source? The vast majority of kerosene-oxygen rockets have be

Always problematic to paraphrase Donald Rumsfeld, but you go to war with the army you have, not the army you'd like to have. You don't get to wish you had a new Apollo program so you could re-invent the rocket from scratch. Your goal, if you actually want to go to space instead of dreaming of the stars, is to make the best of the tools you have, improving them as you can.

I really need to point out that I was answering *your* question? If you don't like the truth, that's not my problem.